www.baidu.com+base64 aHR0cDovL3d3dy5iYWlkdS5jb20=

迅雷  
thunder:// + AAwww.baidu.comZZ
thunder://QUFodHRwOi8vd3d3LmJhaWR1LmNvbVpa

快车  
flashget:// + [FLASHGET]http://www.baidu.com[FLASHGET]
flashget://W0ZMQVNIR0VUXWh0dHA6Ly93d3cuYmFpZHUuY29tW0ZMQVNIR0VUXQ==

腾讯  
qqdl:// + http://www.baidu.com
qqdl://aHR0cDovL3d3dy5iYWlkdS5jb20=

RayFile
fs2you:// + http://www.baidu.com
fs2you://aHR0cDovL3d3dy5iYWlkdS5jb20=

转完一切OK！ 写个WEB版的和Form版的。。。
超级简单的。。。。

private void button1_Click(object sender, EventArgs e)
{
byte[] bytes = Encoding.Default.GetBytes(UrlTextBox.Text);
string str = Convert.ToBase64String(bytes);
Results_TextBox.Text = str;

}

private void button2_Click(object sender, EventArgs e)
{
byte[] bytes = Convert.FromBase64String(UrlTextBox.Text);
Results_TextBox.Text = Encoding.Default.GetString(bytes);
}